Is this a problem or am I just paranoid?

[kellmike626]

Hi guys. This forum has helped me to get to know my engine quite well. I hope you guys can help me out.

So, to start off, I have a 2005 Bayliner 175, equipped with an 05 3.0L Mercruiser Engine and Alpha I Gen II Outdrive. I am the second owner, and well, the first owner (4 years) didn't do much to it, as in the didn't keep up with some of the maintenance. For winterization he just drained the water from the engine.


Engine runs pretty much flawlessly. Shifts fine from Forward-Neutral-Reverse, planes with no problem, and I can top out at W.O.T with no issues whatsoever. No leaks anywhere, everything is fine, at least I think..
Keep in mind, I've only had this boat since last September. I did winterize it correctly.
Now, ever since the season started, I've been getting this noise (almost sounds like a ticking sound, but not that experienced with engines so I have no idea how to describe it). This sound only comes between 650-2000 RPMs, after that it's disappeared, and when going back to idle, it sometimes disappears for the rest of the time.
Sometimes the noise doesn't even come at all..
I have provided a video (it's mainly just the camcorder sitting there beside the engine, but the sound is clearly noticeable. Coming from the port side, near the top of the engine. I give a quick glimpse of the gauges at the end)
http://www.youtube.com/watch?v=UUtzLsWf-b8
Now, am I just being paranoid? Or is this going to become a problem? I know 3 litre engines aren't meant to be quiet, but this is frustrating me as the sound gets annoying sometimes.
Thanks for any input

 

[davemoore]

Re: Is this a problem or am I just paranoid?

I'm not a professional by any means, but I did grow up wrenching on motors...

I'd bet 20 bucks it needs a valve adjustment... sounds kinda' like the rocker arms slapping - loose clearances that tighten up when the RPMs go up...

Again, just a guess...

 

[Howard Sterndrive]

Re: Is this a problem or am I just paranoid?

sounds like an exhaust leak. could try retorquing the manifold, and or replacing gasket.

 

[itsneverfinished]

Re: Is this a problem or am I just paranoid?

sounds like an exhaust leak. could try retorquing the manifold, and or replacing gasket.

an exhaust leak and valves tapping will sound exactly alike IMO.

can you see the exhaust gasket? if you can see the edge of the material you may see it deformed or blown out.

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

an exhaust leak and valves tapping will sound exactly alike IMO.

can you see the exhaust gasket? if you can see the edge of the material you may see it deformed or blown out.

Thank you guys for all the suggestions.

I haven't checked out the exhaust gasket yet. I can't now because it's too dark to see anything.
How do i also check the valve to see if it's tapping?

I'll be sure to check up on these two things in the morning. I've got company coming most likely in the afternoon so i want to try and figure this out before then.

 

[Captain Jaxon]

Re: Is this a problem or am I just paranoid?

Sounds like a rocker arm tapping. Does it go away when it gets warm?

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

Sounds like a rocker arm tapping. Does it go away when it gets warm?

Well, on a cold start, I let the engine warm up to operating temp. After about 10 minutes of running the engine, the tapping occurs (that's a rough estimate). Sometimes it doesn't show up when i operate the engine at low RPM at all for the duration of the boat ride, but i could start it back up and it's there. Once it's there, doesn't go away until I get up to higher RPMs (2000+) and then when I bring the throttle back, sometimes it's disappeared, sometimes it comes back. Usually this happens when the engine is at operating temp or close to it.
When i do a cold start (the next day) I don't hear any tapping at all, but the tapping is happening shortly after the engine's finished warming up to operating temp.
I've always heard it when the engine is at operating temp. When it's warming up I've never even heard the tapping. Hope that answers your question.

But the explanation I'm giving above is mostly leaning towards the rocker arm and/or valve tapping. If it was an exhaust leak, wouldn't it be noticeable regardless? Forgive me if I'm wrong.

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

1. Run engine until it reaches normal operating temperature, then remove valve cover.
2. With engine running at idle, loosen valve rocker arm nut until valve rocker arm starts to clatter.
3. Turn rocker arm nut down slowly until clatter just stops. This is zero lash position.
4. Tighten nut 1/4 additional turn and pause 10 seconds until engine runs smoothly. Repeat additional 1/4 turns, pausing 10 seconds each time, until nut has been tightened 3/4 turn from zero lash position.

I ended up finding this in another post with a guy I'm pretty sure had the same problem. Only difference is the guy rebuilt his engine and had the problem beforehand too. For reference: http://forums.iboats.com/showthread.php?t=393856
If this could fix the problem, do i need special tools?
EDIT: Found out where that valve cover was.

 

[Fireman431]

Re: Is this a problem or am I just paranoid?

If it was/is an exhaust gasket, the sound would not be intermittant. More than likely it's in the valve train.

Since the noise is intermittant, I would lean towards a lifter not pumping up under warm oil conditions. Cold oil is heavier than warm oil. When the oil heats up, it becomes thinner, thereby allowing the lifter to lose some of its volume, creating a clattering noise. this is based strictly on my knowledge of engines and not on your boat or engine conditions.

Personally (just from the video) it sounds like lifter or valve noise. Did you change the oil after winterizing? Did you check to see if there is water in the oil (it will look like chocolate milk)? Did you put the proper weight oil back in after changing it?

If it were mine, my first step would be to verify the condition of the oil (no water). Second, I would drain the oil and change the filter, making sure I had the correct OEM filter and the proper weight oil recommended by the engine manufacturer. Standard 30 weight auto oil is usually not the oil of choice for marine use.

Third, get a proper service manual for your engine. No offense, but if you aren't able to locate the valve cover, how would you plan on adjusting valve lash?

As a side note, wide open throttle is OK on occasion, but not for constant use. That's a great way to over work that little engine and cause yourself a lot of big headaches. Most engines have a sweet spot (3/4 throttle...give or take) for optimum performance. You might lose 3-5 MPH, but you'll burn half the fuel at that speed and prolong the life of your engine.

Talk to a marine mechanic and get some pointers on maintenance. And get that manual.

Let us know how things work out.

 

[macr6]

Re: Is this a problem or am I just paranoid?

^+1
Definitely get yourself a service manual. I did that and it helped me loads. The valve adjustment is an easy job if you are comfortable around tools. You may need a new gasket on the valve cover so you may want to have that handy before you start. I believe the only tools you need are a socket set if I can remember right. Oh and a buch of rags to wipe up the mess you'll make.

Good luck.

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

If it was/is an exhaust gasket, the sound would not be intermittant. More than likely it's in the valve train.

Since the noise is intermittant, I would lean towards a lifter not pumping up under warm oil conditions. Cold oil is heavier than warm oil. When the oil heats up, it becomes thinner, thereby allowing the lifter to lose some of its volume, creating a clattering noise. this is based strictly on my knowledge of engines and not on your boat or engine conditions.

Personally (just from the video) it sounds like lifter or valve noise. Did you change the oil after winterizing? Did you check to see if there is water in the oil (it will look like chocolate milk)? Did you put the proper weight oil back in after changing it?

If it were mine, my first step would be to verify the condition of the oil (no water). Second, I would drain the oil and change the filter, making sure I had the correct OEM filter and the proper weight oil recommended by the engine manufacturer. Standard 30 weight auto oil is usually not the oil of choice for marine use.

Third, get a proper service manual for your engine. No offense, but if you aren't able to locate the valve cover, how would you plan on adjusting valve lash?

As a side note, wide open throttle is OK on occasion, but not for constant use. That's a great way to over work that little engine and cause yourself a lot of big headaches. Most engines have a sweet spot (3/4 throttle...give or take) for optimum performance. You might lose 3-5 MPH, but you'll burn half the fuel at that speed and prolong the life of your engine.

Talk to a marine mechanic and get some pointers on maintenance. And get that manual.

Let us know how things work out.

Water in the oil was the first thing I checked. Looks completely fine, doesn't look milky at all, and it's in the OK range.
As for the type of oil used, I used Quicksilver 4 cycle Marine engine oil (25W40) I changed the oil at the end of last season when winterizing, along with the oil filter, which was from a merc dealer.
Is there any site out there that offers the service manual for free? Or do i have to go to a dealer and buy one? I've noticed the manual links have been taken down in the Adults Only section, which is why i ask.

I usually keep my throttle at 3/4 or under anyways. I don't run at WOT for more than 5-10 seconds at a time when i do happen to. I just happened to mention that the engines run fine regardless of the performance and position of the throttle. I didn't run the engine hard in the video either.

Thanks macr. I got a set of sockets lying around, and once I get the manual I'll be sure to tackle the problem.

 

[6meter]

Re: Is this a problem or am I just paranoid?

Being that it changes, I would say you have a bad lifter. Start it, if noise is there, shut it off and pull the valve cover off. One rocker arm should be loose. I would inspect that rocker, push rod, valve guide, valve spring and lifter. Something there is not right. HTH

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

Thanks for the reply 6meter. I will do that asap.
I now know where the valve cover is (thanks to a diagram, silly me ) but since I've never done it before I'm going to see if I can get some help with this

Again, thanks guys for all the replies. I'll update soon!

 

[BurntOrngeLonghorn84]

Re: Is this a problem or am I just paranoid?

To the OP: did you get your issue resolved. I found your youtube video and I'm experiencing the same issues.

Exact same motor and year, just a little bit bigger boat (195).

Mine is not intermittent so can i feel around the exhaust for a leak, or is it best to do a visual inspection?

 

[StevNimrod]

Re: Is this a problem or am I just paranoid?

Thanks for the reply 6meter. I will do that asap.
I now know where the valve cover is (thanks to a diagram, silly me ) but since I've never done it before I'm going to see if I can get some help with this

Again, thanks guys for all the replies. I'll update soon!

It might help to take a length of rubber hose (or stethoscope), hold it up to your ear and put the other end at various places on the engine. It will help you pinpoint the area whether it's the top (near the valves covers), bottom, left, right, etc.

Especially if it's a valve train problem, you'll hear when you hit paydirt.

 

[korygrandy]

Re: Is this a problem or am I just paranoid?

Just curious if the OP figured out the problem. My 3.0l does the same thing. Hard to believe so many people with the 3.0l have bad rocker arms.

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

I didn't know this was becoming a problem for lots of people. I don't know whether it's bad rocker arms or if they just come out of adjustment easily. Either way, it's annoying to listen to.

To those wondering, I have not done the job yet, simply because I have to pick up a valve cover gasket before I do it as it's going to need to be replaced. Didn't have time last week to pick it up. Before you do it, make sure you have a good area to work in. It's a messy job from what I've heard.

BurntOrnge, you won't be able to see the loose rocker unless you remove the valve cover while running the engine (that's only if you have the exact same issue) and it should be easy to spot. You can hear it otherwise, but go with StevNimrod's suggestion on pinpointing where the noise is with a stethoscope before opening anything, as that's what I'm going to do beforehand. I have confirmed it is the rocker myself, and i'd probably be nowhere right now without the help

 

[sethjon]

Re: Is this a problem or am I just paranoid?

Check the obvious first. Hows the oil level? Also, what type of oil are you using?

 

[paultjohnson]

Re: Is this a problem or am I just paranoid?

It does sound like a lifter tick Just a little to much slop between the rocker and the pushrod. Great idea from other posters to locate w a makeshift stethascope. Also ,after you take the valve cover off put a glove on and just push down on each individual rocker arm with the ball of your hand with the engine running, thats often enough to take away the slop to determine which rocker is ticking. Have done it on many cars, when you push on the loose one it will quite right down and you will know which rocker needs to be snugged. Also when the valve cover is off make sure all the oil passages are open, no crud or crap blocking oil flow. You also may wanna try some seafoam or somethong in the crankcase to free uo anything thats gunked up and sticking in the valve train. Some old school ideas good luck

 

[kellmike626]

Re: Is this a problem or am I just paranoid?

Check the obvious first. Hows the oil level? Also, what type of oil are you using?

You might have missed it, but the level of oil is right at the full mark. I use the recommended Quicksilver 25W40 Marine Engine Oil, and all the recommended filters too. Not dark or milky either.

Thanks again guys for the suggestions. I'll update when I get it all fixed up.